DESIGN OPTIMIZATION OF HYDROSTATIC WORKTABLE BASED ON MULTI-LAYER METHOD OF FEASIBLE DIRECTION

To improve the dynamic performance of a hydrostatic worktable, this paper gives a formula of hydrodynamic loads at a hydrostatic recesses firstly. Next the static bearing capacity load of an oil film from an oil pump at the same recesses is calculated. Then both dynamic and static bearing capacity loads are integrated as a formula. Based on the formula, the oil film stiffness is inferred. On the next stage, an optimization design model of a benchmark hydrostatic worktable system is established, in which the optimal target is to maximize integrated bearing capacity loads and oil film stiffness mentioned above, and the constraint is the frequency at the first order. Next response surface methodology and multi-layer method of a feasible direction are applied to solve the optimal model. Finally, the analysis for time history response under a transient impact load is completed to check over the working accuracy of a finished optimal structure. Overall the optimal results and methodology provide a theoretical basis in new generation design of practical structures.